PERF: avoid preloading json in cases where it is not needed

(uploads / avatars / non GET requests)

app/controllers/draft_controller.rb

@@ -1,6 +1,7 @@
 class DraftController < ApplicationController
   before_filter :ensure_logged_in
-  skip_before_filter :check_xhr
+  # TODO really do we need to skip this?
+  skip_before_filter :check_xhr, :preload_json
 
   def show
     seq = params[:sequence] || DraftSequence.current(current_user, params[:draft_key])